I couldn't understand where your maths was going wrong until I realised my conversion of 1800mm to old inches is wrong
Sorry, should have read 71'' rudder to centre of rear support.
Anyway, the 222'' is the hull-only length, so minus (65+67) = 90'' front overhang.
On my trailer there is an additional small v-shaped support for the bow just in front of the snubber.
But in my garage I only have the two supports, spaced as above on hoists.
I don't worry about missing the 3rd support in the garage, as the temperature is low & constant, and no direct heat from the sun.
Not sure what to advise for transporting, I wouldn't want to be the one who says it's ok if it then turns out not to be!
All I'd say is that most people seem to transport large tandem SOTs on 2 roof bars without too much bother?
Just don't pull down too hard on any strap from the bow, and don't park up in the hot sun?